rectangle(), drawpoly()

#include < graphics.h > 
#include < stdio.h > 
int main() {
    int i;
    int points[8] = {
        320,
        0,
        0,
        240,
        640,
        240,
        320,
        0
    };
    int graphdriver = DETECT;
    int graphmode;
    initgraph( & graphdriver, &graphmode, "");
    cleardevice();
    rectangle(0, 0, getmaxx(), getmaxy());
    drawpoly(4, points);
    getch();
    cleardevice();
    drawpoly(3, points);
    getch();
    closegraph();
    return 0;
}